Manufacture of valuable products from lignin sulphonic acid (sulphite cellulose waste)



Patented June 30, .1931

UNITED STATESPATENT OFFICE JAMES BADDILEY, ARNOLD SHEPHERZDSON, AND ANTHONY JAMES HAILWOOD, OF

' BLACKLEY, MANCHESTER, ENGLAND, ASSIGNORS T BRITISH DYESTUFFS CORPORA- TION LIMITED, OF MANCHESTER, ENGLAND MANUFACTURE OF VALUABLE PRODUCTS FROM LIGNIN SULPHONIC ACID (SULPHITE CELLULOSE WASTE) v Ho Drawing. Application filed September 9, 1927,

We have now found that by treating the ordinary commercial sulphite cellulose pitch in aqueous solution with oxidizing agents, new compounds are formed which differ from 5 the original sulphite cellulose waste in that do not give the Schifi reaction for aldethe hydes, and whereas the cellulose waste liquor in neutral dilute solution only gives a faint precipitate with barium chloride solution, the new products give a copious precipitate which can be filtered ofi' and is soluble in hydrochloric acid. A further distinction is that although sulphitc cellulose pitch reduces indigo in the presence of weak aqueous.

1 sodium hydroxide, the new products do not. The new products possess in an enhanced degree the valuable dispersing and solubilizing properties of sulphite cellulose pitch .and 'moreover have the important additional advantage of forming, when dried,- a friable and non-hygroscopic mass. They find application in dyestufi preparations, whether as powder or as paste, the effect of their presence being to keep the dyestufi in easily dispersible form and to prevent coagulation and settling of dyestuff pastes. When added to an already disperseddyestufi paste they enablethe paste to be dried at moderately high'temper- -atures to a powder which retains its power todisperse readily in water. Our products fur- '=ther find application in vat dye preparations,

and in the dyeing of acetate silk.

Serial 110.. 218,569, and in Great Britain December bath. Considerable gas evolution occurs as evaporation proceeds, and ultimately no free nitric acid remains.

The product, which shows an acid reaction to litmus, may either be neutralized with ammonia and evaporated to dryness, or used directly.

What we claim and desire to secure by Letters Patent is 1. In combination a dyestufi paste or powder and theproduct of the moderated oxidation of sul hite cellulose itch vwith nitric acid, the said combination eing characterized by ready dispersibility in water.

2. In combination, a -d estuif astev or powder, and the product 0 the oxi ation of sulphite cellulose pitch with nitric acid a boiling temperature, the said combinationbeing characterized by ready dispersibility in 'water.- y

3. "In combination, a 'dyestufi paste orpowder, and the product of the moderate oxidation of sulphite cellulose pitch with diluted nitricacid at boiling temperature, the

said combination beingcharacterized b 'readydispersibility in water.

natures; 1 I a JAMES BADDILEY.

.. ARNOLD. SHEPHERDSQN.

ANTHONY It has been proposed to convert sulphite cellulose pitch by oxidation into oxalic acid using a large proportion of concentrate nitric acid. In our invention, on the other hand,we moderate the degree of oxidation so as to avoid the formation of oxalic acid,"

In testimony whereof we. aiiix our sig-' 

